Predictors of next day discharge following total hip arthroplasty using the direct anterior approach

Abstract

Total hip arthroplasty widely considered to be the “operation of the 20th century” is projected to increase in number over the coming decades. This is a life changing operation with significant risks and benefits available to the patient should they choose to opt for this course of treatment. The direct anterior approach is fast becoming a popular and sought after approach by surgeons and patients alike due to its propensity for greater soft tissue management and potential to mobilise sooner post-operatively. The aim of this research dissertation is to determine the predictive factors of next day discharge following total hip arthroplasty using the direct anterior approach. A Cross-sectional retrospective study was performed at a single private practice in Johannesburg, South Africa. The study population included all patients over a six-year period (01 January 2016 – 31 December 2021) who have undergone Direct Anterior Approach (DAA) for Total Hip Arthroplasty (THA) at Morningside Mediclinic. The data consisted of 700 records and 12 variables namely; next day discharge, age, sex, Body Mass Index (BMI), side of surgery, American Society of Anaesthesiologists (ASA) grade, anaesthetic method, time of surgery, Timed up-and-go (TUG), Risk Assessment and Prediction Tool (RAPT), Harris Hip Scale (HHS), and grip strength. Of a possible 9100 data points there were a total of 396 missing observations. Of the data analysed the most statistically significant findings were that female patients, who are over the age of 70 years, have had surgery in the afternoon and were exposed to general anaesthetic, are more likely to have longer length of stay. This was confirmed by various pre- operative and validated assessment tools. Subsequently, an exploratory analysis found that grip strength, which is now widely considered to be the new vital sign of health, could be used as an inexpensive point of care test to predict next day discharge following THA via the DAA.